This application claims the benefit of Korean Application No. 99-37307, filed Sep. 3, 1999, in the Korean Patent Office, the disclosure of which is incorporated herein by reference.
1. Field of the Invention
The present invention relates to the field of moving pictures, and more particularly, to an apparatus and method for recording and/or reproducing state information associated with audio for moving pictures, and a recording medium for storing audio state information.
2. Description of the Related Art
Development in the field of digital compression techniques and increases in the capacity of recording media are now enabling moving picture information to be compressed into digital data and recorded. Compression techniques include a variety of standards. In the case of video, the MPEG (moving picture experts group)-2 video (ISO/IEC 13818-2) MP@ML (Main Profile at Main Level) standard, which has the same image quality as current analog televisions, is now the most widely used. The use of the MPEG-2 MP@HL (Main Profile at High Level) standard, which is capable of achieving the image quality of high definition television (HDTV) is rapidly increasing. In the case of audio, AC (Audio Coding)-3 is generally used around North America, and the MPEGxc2xd Audio (ISO/IEC13818-3) standard is being used in Europe. The amount of audio data is less than that of video data, so that the linear pulse code modulation (LPCM) standard, in which there is no compression can also be used for audio.
In this way, audio data and video data are signal-processed in accordance with respective standards, and then combined into data of a bitstream. At this time, the MPEG-2 System (ISO/IEC 13818-1) standard is generally used. That is, each of the audio data and the video data is packeted, and discrimination information for discriminating between audio and video, buffer control information, and timing information for synchronizing an audio signal with a video signal, are added to each packet. Timing information related to a clock signal to be used by a decoder is also added to each packet, resulting in pack data. Here, the digital versatile disc (DVD) video standard prescribes that the size of one pack of data is 2048 bytes.
A general moving picture recording apparatus includes several important functions among which there is an after recording function of later replacing and overwriting only an audio portion among moving picture data which has already been recorded on a recording medium. Existing analog recording media have tracks on which video signals for moving pictures and audio signals are separately recorded, such that the after recording function is easily performed. Also, an analog signal is not recorded in a particular recording unit, so that operations required for the after recording are completed by overwriting a desired portion.
Here, audio which has been originally recorded is called original audio, and audio to be replaced and recorded later is called secondary audio. In order to preserve original audio upon recording of secondary audio, two audio tracks to separately record the original audio and the secondary audio must be prepared. Accordingly, original audio and secondary audio are discriminated from each another by the positions of their tracks.
While the two tracks are simultaneously played back, the secondary audio signal is only output when an audio signal exists in the track for secondary audio, and otherwise, an audio signal existing in the track for original audio is output. In this way, secondary audio which has been partially recorded on a track can be reproduced. When reproduction of only the original audio is desired, an audio signal on the original audio track can be reproduced independently of the existence or non-existence of audio signals on the secondary audio track.
However, in the digital recording medium, audio/video (A/V) signals have been mixed and recorded on a recording area in a predetermined recording unit without classification, such that recording and reproducing of secondary audio using the overwriting method used by the analog recording medium is not possible.
To solve the above problem, an object of the present invention is to provide a recording medium for dividing moving picture data into a plurality of basic units, generating basic unit information, which is required for reproduction/edition and included in each basic unit, and storing audio state information in the basic unit information.
Another object of the present invention is to provide a recording apparatus for dividing moving picture data into a plurality of basic units, generating basic unit information related to each basic unit, and storing audio state information in the basic unit information.
Still another object of the present invention is to provide a reproducing apparatus for selectively reproducing original audio or secondary audio on the basis of audio state information.
Yet another object of the present invention is to provide a recording method of dividing moving picture data into a plurality of basic units, generating basic unit information related to each basic unit, and storing audio state information in the basic unit information.
Still yet another object of the present invention is to provide a reproducing method of selectively reproducing original audio or secondary audio on the basis of audio state information.
Additional objects and advantages of the invention will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the invention.
To achieve the first and other objects of the present invention, there is provided a recording medium on which a moving image is divided into a plurality of basic units and recorded, and basic unit information related to the moving image is recorded in each basic unit, wherein the basic unit is comprised of at least one among video data, audio data and graphic data, and the audio data is comprised of first audio or first audio and second audio; the basic unit information includes the state information on the first audio and the state information on the second audio; the state information on the first audio represents an original audio state in which the first audio is original audio, or a secondary audio state in which the first audio is secondary audio recorded over part or all of the original audio; and the state information on the second audio represents a state in which the second audio is original audio, a state in which the second audio is secondary audio recorded over part or all of the original audio, a state in which the second audio is dummy audio which is exactly the same as the first audio, or a state in which the second audio is secondary audio recorded over part or all of the dummy audio.
To achieve the second and other objects of the present invention, there is provided a moving picture recording apparatus by which a moving image is divided into a plurality of basic units and recorded, basic unit information related to the moving image is recorded on each basic unit, and the basic unit is comprised of at least one among video data, audio data and graphic data. The apparatus includes a recording controller by which first audio or first audio and second audio is recorded as the audio data, the state information on the first audio and the state information on the second audio are recorded as the basic unit information, the state information on the first audio represents an original audio state in which the first audio is original audio, and when the second audio exists, the state information on the second audio represents a state in which the second audio is original audio, or a state in which the second audio is dummy audio which is exactly the same as the first audio.
To achieve the third and other objects of the present invention, there is provided an apparatus for playing back a recording medium on which a moving picture is divided into a plurality of basic units and recorded, basic unit information related to the moving image is recorded in each basic unit, each of the basic units is comprised of at least one among video data, audio data and graphic data among which the audio data is comprised of first audio, or first audio and second audio, the basic unit information includes the state information on the first audio and the state information of the second audio, the state information on the first audio represents a state in which the first audio is original audio, or a state in which the first audio is secondary audio recorded over part or all of the original audio, and the state information on the second audio represents a state in which the second audio is original audio, a state in which the second audio is secondary audio recorded over part or all of the original audio, a state in which the second audio is dummy audio which is exactly the same as the first audio, or a state in which the second audio is secondary audio recorded over part or all of the dummy audio. The apparatus includes a reproducing controller for reproducing the original audio and secondary audio according to the first audio state information/second audio state information.
To achieve the fourth and other objects of the present invention, there is provided a moving picture recording method by which a moving image is divided into a plurality of basic units and recorded, basic unit information related to the moving image is recorded on each basic unit, and the basic unit is comprised of at least one among video data, audio data and graphic data. The method includes recording first audio or first audio and second audio as the audio data, and recording the state information on the first audio and the state information on the second audio as the basic unit information, wherein the state information on the first audio represents an original audio state in which the first audio is original audio, and when the second audio exists, the state information on the second audio represents a state in which the second audio is original audio, or a state in which the second audio is dummy audio which is exactly the same as the first audio.
To achieve the fifth and other objects of the present invention, there is provided a method of playing back a recording medium on which a moving picture is divided into a plurality of basic units and recorded, basic unit information related to the moving image is recorded in each basic unit, each of the basic units is comprised of at least one among video data, audio data and graphic data among which the audio data is comprised of first audio, or first audio and second audio, the basic unit information includes the state information on the first audio and the state information of the second audio, the state information on the first audio represents a state in which the first audio is original audio, or a state in which the first audio is secondary audio recorded over part or all of the original audio, and the state information on the second audio represents a state in which the second audio is original audio, a state in which the second audio is secondary audio recorded over part or all of the original audio, a state in which the second audio is dummy audio which is exactly the same as the first audio, or a state in which the second audio is secondary audio recorded over part or all of the dummy audio. The method includes analyzing the first audio state information/second audio state information, and reproducing the original audio/secondary audio according to the analyzed audio state information.